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Scientists Predict Devastation if Asteroid Bennu Strikes Earth in 2182

FILE - This May 18, 1969 photo provided by NASA shows Earth from 36,000 nautical miles away as photographed from the Apollo 10 spacecraft during its trans-lunar journey toward the moon. (NASA via AP)
FILE - This May 18, 1969 photo provided by NASA shows Earth from 36,000 nautical miles away as photographed from the Apollo 10 spacecraft during its trans-lunar journey toward the moon. (NASA via AP)
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Scientists Predict Devastation if Asteroid Bennu Strikes Earth in 2182

FILE - This May 18, 1969 photo provided by NASA shows Earth from 36,000 nautical miles away as photographed from the Apollo 10 spacecraft during its trans-lunar journey toward the moon. (NASA via AP)
FILE - This May 18, 1969 photo provided by NASA shows Earth from 36,000 nautical miles away as photographed from the Apollo 10 spacecraft during its trans-lunar journey toward the moon. (NASA via AP)

The rocky object called Bennu is classified as a near-Earth asteroid, currently making its closest approach to Earth every six years at about 186,000 miles (299,000 km) away. It might come even closer in the future, with scientists estimating a one-in-2,700 chance of a collision with Earth in September 2182, Reuters reported.
So what would happen should Bennu strike our planet? Well, it would not be pretty, according to new research based on computer simulations of an impact by an asteroid with a diameter of roughly three-tenths of a mile (500 meters) like Bennu.
Aside from the immediate devastation, it estimated that such an impact would inject 100-400 million tons of dust into the atmosphere, causing disruptions in climate, atmospheric chemistry and global photosynthesis lasting three to four years.
"The solar dimming due to dust would cause an abrupt global 'impact winter' characterized by reduced sunlight, cold temperature and decreased precipitation at the surface," said Lan Dai, a postdoctoral research fellow at the IBS Center for Climate Physics (ICCP) at Pusan National University in South Korea and lead author of the study published this week in the journal Science Advances.
In the worst-case scenario, the researchers found that Earth's average surface temperature would decrease by about 7 degrees Fahrenheit (4 degrees Celsius), average rainfall would fall by 15%, there would be a reduction of up to 20-30% in plant photosynthesis and a 32% depletion in the planet's ozone layer that protects against harmful solar ultraviolet radiation.
The impact of a Bennu-sized object - a medium-sized asteroid - on Earth's land surface would generate a powerful shockwave, earthquakes, wildfires and thermal radiation, leave a gaping crater and eject huge amounts of debris upward, the researchers said.
Large quantities of aerosols and gases would reach the upper atmosphere, causing years-long effects on climate and ecosystems, according to Dai and study senior author Axel Timmermann, a climate physicist and ICCP director.
The unfavorable climate conditions would inhibit plant growth on land and in the ocean, they said.
"In contrast to the rapid reduction and slow two-year-long recovery of plants on land, plankton in the ocean would recover within six months - and even increase afterward with unprecedented diatom (a type of algae) blooms triggered by iron-rich dust deposition into the ocean," Dai said.
Severe ozone depletion would occur in the stratosphere - the second atmospheric layer as you go upward - due to strong warming caused by the solar absorption of dust particles, the researchers said.
An asteroid collision of this magnitude could cause massive loss of human life, but that calculation was outside the study's scope. Dai said the potential death toll "mainly depends on where the asteroid impact occurs."
Scientists know a great deal about Bennu, considered a "rubble pile" asteroid - a loose amalgamation of rocky material rather than a solid object. It is a rocky remnant of a larger celestial body that had formed near the dawn of the solar system roughly 4.5 billion years ago. NASA's robotic OSIRIS-REx spacecraft journeyed to Bennu and in 2020 collected samples of rock and dust for analysis.
A study published in January showed that Bennu's samples bore some of the chemical building blocks of life, strong evidence that asteroids may have seeded early Earth with the raw ingredients that fostered the emergence of living organisms.
Asteroids have struck Earth occasionally over its long history, often with cataclysmic results. An asteroid estimated at 6-9 miles (10-15 km) wide hit off the coast of Mexico's Yucatan Peninsula 66 million years ago, eradicating about three-quarters of the world's species and ending the age of dinosaurs.
NASA in 2022 carried out a proof-of-principle planetary defense mission by using its robotic DART spacecraft to change the trajectory of the asteroid Dimorphos, with an eye toward doing this in the future if one appears on a collision course with Earth.
"The likelihood that a Bennu-sized asteroid will strike Earth is quite small at 0.037%. Even though small, the potential impact would be very serious and would likely lead to massive longer-term food insecurity on our planet and climate conditions that are similar to those seen only for some of the largest volcanic eruptions in the last 100,000 years," Timmermann said.
"So it is important to think about the risk," Timmermann added.

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Dinosaur Fossils in Brazil Reveal New Giant Species

An employee works at the excavation site where dinosaur bones were found in Davinopolis, Maranhao state, Brazil, April 28, 2021. Giovani de Toledo Viecili/Handout via REUTERS
An employee works at the excavation site where dinosaur bones were found in Davinopolis, Maranhao state, Brazil, April 28, 2021. Giovani de Toledo Viecili/Handout via REUTERS
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Dinosaur Fossils in Brazil Reveal New Giant Species

An employee works at the excavation site where dinosaur bones were found in Davinopolis, Maranhao state, Brazil, April 28, 2021. Giovani de Toledo Viecili/Handout via REUTERS
An employee works at the excavation site where dinosaur bones were found in Davinopolis, Maranhao state, Brazil, April 28, 2021. Giovani de Toledo Viecili/Handout via REUTERS

Brazilian scientists have identified a new species of giant dinosaur with ties to a similar animal found in Spain, reinforcing knowledge that land routes once connected parts of South America, Africa and Europe about 120 million years ago.

Named Dasosaurus tocantinensis, the species is one of the biggest found in the South American country and was described this month in the Journal of Systematic Palaeontology, Reuters reported.

The fossils were uncovered in 2021 at a site hosting infrastructure works near Davinopolis, in Brazil's northeastern state of Maranhao, and the research was led by Elver Mayer of the Federal University of the Sao Francisco Valley.

The remains include a femur measuring about 1.5 meters (59 inches), which helped researchers estimate the animal stretched roughly 20 meters long.

"As the excavation progressed over the days, we began to see the evidence of that huge bone, which is the femur," said Leonardo Kerber, a paleontologist at the Federal University of Santa Maria (UFSM) who contributed to the research.

"This indicates it was a very large dinosaur. Today we know Dasosaurus is among the biggest dinosaurs ever found in Brazil," he noted.

According to UFSM, analysis indicated the species is the closest known relative of Garumbatitan morellensis, a dinosaur described in Spain.

Their lineage was European and may have dispersed into what is now South America roughly 130 million years ago, likely via northern Africa, before the Atlantic fully opened, the university said.

Dasosaurus tocantinensis's name combines references to the region where the dinosaur was found, including the Tocantins River, a major waterway whose eastern margins lie near the fossil site.

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German Philosopher Jurgen Habermas Dies Age 96

German philosopher Professor Juergen Habermas makes a speech during the awards ceremony for the "Understanding and Tolerance" prize at the Jewish museum in Berlin, November 13, 2010. REUTERS/Odd Andersen/Pool/File Photo
German philosopher Professor Juergen Habermas makes a speech during the awards ceremony for the "Understanding and Tolerance" prize at the Jewish museum in Berlin, November 13, 2010. REUTERS/Odd Andersen/Pool/File Photo
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German Philosopher Jurgen Habermas Dies Age 96

German philosopher Professor Juergen Habermas makes a speech during the awards ceremony for the "Understanding and Tolerance" prize at the Jewish museum in Berlin, November 13, 2010. REUTERS/Odd Andersen/Pool/File Photo
German philosopher Professor Juergen Habermas makes a speech during the awards ceremony for the "Understanding and Tolerance" prize at the Jewish museum in Berlin, November 13, 2010. REUTERS/Odd Andersen/Pool/File Photo

The German philosopher Jurgen Habermas has died, a spokesperson for his publishing house, Suhrkamp Verlag, told AFP on Saturday.

He died at the age of 96 in Starnberg, in southern Germany, she said, citing information from the family of the politically engaged theorist.

Habermas was considered the most influential German philosopher of his generation, involved in all the major postwar debates and seeing a united Europe, in his view, as the only remedy for the rise of nationalism, AFP reported.

In his later years, he devoted himself to promoting a federal European project and prevent the continent from falling, as it did in the 20th century, into nationalist rivalries.

Throughout his life, Habermas linked philosophy and politics, thought and action.

After serving as the voice of German student protest in the 1960s, he became its target thirty years later while warning of the risks of "left-wing fascism".

In 1989, he criticised the terms of German reunification, guided essentially by the demands of the market, and which made "the Deutsche mark its standard."

Born on June 18, 1929 in Duesseldorf, Habermas had been enrolled in the Hitler Youth, but he was too young to have taken an active part in the war. As a teenager, he was deeply marked by the collapse of Nazism.

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Research Reveals Decades-Long Silverpit Crater Triggered by Tsunami 40 Million Years Ago

A massive asteroid struck the North Sea millions of years ago (Getty)
A massive asteroid struck the North Sea millions of years ago (Getty)
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Research Reveals Decades-Long Silverpit Crater Triggered by Tsunami 40 Million Years Ago

A massive asteroid struck the North Sea millions of years ago (Getty)
A massive asteroid struck the North Sea millions of years ago (Getty)

A long-running dispute about the origin of a North Sea crater has finally been settled, as new research finds a massive asteroid hit the water and triggered a towering tsunami millions of years ago.

Scientists have found that the Silverpit Crater – which lies around 700 meters beneath the southern North Sea seabed, roughly 80 miles off the coast of Yorkshire – was formed when an asteroid or comet struck the region roughly 43 to 46 million years ago, sparking a 330 feet tsunami.

Since geologists first identified the formation in 2002, the 3km-wide crater and its surrounding ring of circular faults spanning about 20 km have sparked intense debate, according to The Independent.

But researchers say their new study marks the clearest evidence yet that the structure is one of Earth’s rare impact craters.

This confirmation places it in the same category as well-known structures such as the Chicxulub Crater in Mexico, which is linked to the dinosaur mass extinction.

The team used computer modelling and analyzed newly available seismic imaging and microscopic geological samples taken from beneath the seabed.

Dr. Uisdean Nicholson, a sedimentologist in Heriot-Watt University’s School of Energy, Geoscience, Infrastructure and Society, who led the investigation, said: “New seismic imaging has given us an unprecedented look at the crater.”

He said samples from an oil well in the area also revealed rare ‘shocked’ quartz and feldspar crystals at the same depth as the crater floor.

“We were exceptionally lucky to find these – a real ‘needle-in-a-haystack’ effort. These prove the impact crater hypothesis beyond doubt, because they have a fabric that can only be created by extreme shock pressures,” said Nicholson.

The scientists say these microscopic minerals form only under the extreme pressures generated during asteroid impacts, providing strong confirmation of the event.

Early research proposed that the feature was created by a high-speed asteroid impact. Supporters of that idea pointed to its round shape, central peak, and surrounding concentric faults, which are often seen in known impact craters.

But other scientists suggested different explanations. Some proposed that underground salt movement distorted the rock layers and created the structure.

Others argued that volcanic activity may have caused the seabed to collapse.

In 2009, geologists even voted on the issue. According to a report in the December 2009 issue of Geoscientist magazine, most participants rejected the asteroid impact explanation at the time.

The latest findings, published in the journal Nature Communications and funded by the Natural Environment Research Council (NERC), now appear to overturn that conclusion.

Dr. Nicholson said: “Our evidence shows that a 160-meter-wide asteroid hit the seabed at a low angle from the west.”

“Within minutes, it created a 1.5 km high curtain of rock and water that then collapsed into the sea, creating a tsunami over 100 meters high.”

The impact would have produced a violent explosion at the seafloor and sent enormous waves spreading across the region.

Professor Gareth Collins, of Imperial College London, who attended the 2009 debate about the crater’s origin and contributed to the new research, said the researchers have “finally found the silver bullet” to end the debate.

He said: “I always thought that the impact hypothesis was the simplest explanation and most consistent with the observations.”

“It is very rewarding to have finally found the silver bullet. We can now get on with the exciting job of using the amazing new data to learn more about how impacts shape planets below the surface, which is really hard to do on other planets,” Collins added.

Dr. Nicholson also expressed his excitement about using the new findings for further research into asteroids.

“Silverpit is a rare and exceptionally preserved hypervelocity impact crater,” he said.

“These are rare because the Earth is such a dynamic planet – plate tectonics and erosion destroy almost all traces of most of these events.”